How is linear motion achieved in this automatic blackboard eraser?

Question

In the animation shown below what can be the mechanism used for this purpose? I know it can be achieved by using rack and pnion gear arrangement. But how are this set up arranged in classroom environment, I have no little idea. Please help me about this mechanism. And what can be best suitable material for this wiping action Thanks Video link: https://youtu.be/VB3FGRPSqsI

Answer 1

that is a scanner that converts the writing on the board into a digital file for remote sharing, and then erases the board.

These devices use either a rack-and-pinion gear arrangement with the rack running along the top edge of the board, or a flexible cable-and-pulley system with an electric motor coupled to the pulley through a set of reduction gears.

You can get an excellent idea of how the cable-and-pulley systems work by taking apart an inkjet printer and studying the print carriage transport mechanism; almost all inkjet printers use this arrangement to move the printhead across the paper surface.